Tetra Tech wins $15M CSO abatement project in New York state

PASADENA, CA, August 1, 2007 -- Tetra Tech Inc. announced today that it has been awarded a $15 million combined sewer overflow (CSO) control program in central New York state through The Delaney Group, a recent acquisition. Tetra Tech will provide construction-related services for the first phase of the Clinton Street CSO Abatement Project in Onondaga County, New York.

This project is a critical part of Onondaga County's area-wide CSO control and upgrade program. It will help improve the water quality of Onondaga Lake and help the County comply with state and federal water quality regulations, including the Clean Water Act.

The U.S. Environmental Protection Agency estimates that 850 billion gallons of untreated wastewater and stormwater are released as CSOs each year. Combined sewer systems serve roughly 400 cities with about 40 million people nationwide, mostly in the Northeast and Great Lakes regions. Tetra Tech has been awarded 16 CSO programs in the last two years.

Tetra Tech is a leading provider of consulting, engineering, and technical services. With approximately 7,500 associates located in the United States and internationally, the Company supports commercial and government clients in the areas of resource management and infrastructure. Tetra Tech's services include research and development, applied science and technology, engineering design, program management, construction management, and operations and maintenance.

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